Previous PID Research Articles

Model-Free RBF Neural Network Intelligent-PID Control Applying Adaptive Robust Term for Quadrotor System

This paper proposes a quadrotor system control scheme using an intelligent–proportional–integral–differential control (I-PID)-based controller augmented with a radial basis neural network (RBF neural network) and the proposed adaptive robust term. The I-PID controller, similar to the widely utilized PID controller in quadrotor systems, demonstrates notable robustness. To enhance this robustness further, the time-delay estimation error was compensated with an RBF neural network. Additionally, an adaptive robust term was proposed to address the shortcomings of the neural network system, thereby constructing a more robust controller. This supplementary control input integrated an adaptation term to address significant signal changes and was amalgamated with a reverse saturation filter to remove unnecessary control input during a steady state. The adaptive law of the proposed controller was designed based on Lyapunov stability to satisfy control system stability. To verify the control system, simulations were conducted on a quadrotor system maneuvering along a spiral path in a disturbed environment. The simulation results demonstrate that the proposed controller achieves high tracking performance across all six axes. Therefore, the controller proposed in this paper can be configured similarly to the previous PID controller and shows satisfactory performance.

Active disturbance rejection adaptive fuzzy backstepping control of uncertain flexible marine riser system

In this paper, vibration control of a flexible marine riser with uncertain parameters subjected to distributed disturbance and boundary disturbance is studied. The existing vibration control algorithms have the problems of relying on the accurate mathematical model of the system, complex control laws, and need to measure multiple states of the system, which cannot effectively deal with the uncertainty of model parameters and external disturbances. To effectively suppress the vibration of a marine flexible riser system with uncertain parameters, an adaptive fuzzy backstepping control algorithm was designed. First, the backstepping method and Lyapunov function are used to analyze the subsystem and design the virtual control law. On this basis, an adaptive fuzzy system was designed. The fuzzy system was used to approach the unknown nonlinear term in the design process of the control law and the uniform boundedness of the system was proved by the Lyapunov stability theory. The designed control algorithm has a simple structure, and it can effectively restrain the riser vibration and improve the control rate. Finally, the numerical simulation results show that the designed control algorithm is effective in suppressing the vibration of flexible risers and the control effect is better than previous PID control and robust adaptive control.

Bilateral or unilateral tubo-ovarian abscess: exploring its clinical significance

ObjectivesTo assess the characteristics of patients with unilateral and bilateral tubo-ovarian abscess (TOA).MethodsWomen diagnosed with TOA during 2003–2017 were included in this retrospective cohort study. TOA was diagnosed using sonography or computerized tomography and clinical criteria, or by surgical diagnosis. Demographics, sonographic data, clinical treatment, surgical treatment, and post-operative information were retrieved.ResultsThe study cohort included 144 women who met the inclusion criteria, of whom 78 (54.2%) had unilateral TOA and 66 (45.8%) had bilateral TOA. Baseline characteristics were not different between the groups. There was a statistical trend that women with fewer events of previous PID were less likely to have with bilateral TOA (75.3% vs. 64.1%, respectively; p = 0.074). Women diagnosed with bilateral TOA were more likely to undergo surgical treratment for bilateral salpingo-oophorectomy compared to unilateral TOA (61.5% vs. 42.3%, respectively; p = 0.04). There was no difference in maximum TOA size between groups.ConclusionsThis study detected a trend toward increased need for surgical treatment in women diagnosed with bilateral TOA. These findings may contribute to determining the optimal medical or surgical treatment, potentially leading to a decrease in the duration of hospitalization, antibiotic exposure, and resistance. However, it is important to acknowledge that the results of the current study are limited, and further research is warranted to validate these potential outcomes.

Laparoscopic Approach for the Management of Ectopic Pregnancy in a District Level Hospital, Cox's Bazar

Introduction: An ectopic pregnancy occurs when a fertilized egg implants and grows outside of the uterine cavity. Ectopic pregnancy usually occurs as a result of delay or prevention in the passage of the blastocyst to the uterine cavity resulting in its premature implantation in the extrauterine tissues. It usually occurs in 2% of all pregnancies and is a major cause of maternal morbidity and mortality when misdiagnosed or left untreated and subsequent successful pregnancy is less than 50% of patients. About 95% of ectopic pregnancies originate in the tubes. Infrequently, it affects the ovary, the bicornuate uterus, and the cervix. The diagnosis of ectopic pregnancy has been performed using laparoscopy. Additionally, it is widely used for the surgical treatment of ectopic pregnancy. The benefit of laparoscopy for ectopic pregnancy over laparotomy is well-known. Laparoscopic surgery has been widely adopted and new technical innovations, procedures, and evidence-based knowledge are persistently emerging. The laparoscopic advantage over open surgery has also been confirmed in different fields. It is associated with shorter operative time, less intraoperative blood loss, reduce postoperative pain, less analgesic requirement, a shorter hospital stay, faster recovery, cost- effectiveness, and lower rate of postoperative complications. This study aimed to compare the outcome of laparoscopic management with laparotomy in the management of ectopic pregnancy. Methods: This was a prospective cross-sectional study that was carried out in a district level hospital at Cox's Bazar. This study was conducted from May 2020 to May 2022. A total of 59 subjects were selected for the study as per inclusion criteria. Result: Among 59 respondents, most of the subjects were of the 15-25 years age group which constituted 81.36%, followed by 13.56% of the 26-35 years age group, and the rest 5.08% were of >35 years age group. Laparoscopy was done on 40 (67.20%) patients and laparotomy was done on 19 (32.80%) patients. Approximately, 25% of laparoscopy patients and 52% of laparotomy patients had prior surgery. Prior ectopic surgery was performed on around 8.47% of laparoscopy patients and 13.55% of laparotomy patients. Regarding the comparison of laparoscopy and laparotomy procedure, total blood loss was less (30-50ml) in laparoscopy and more (≥60ml) in the laparotomy procedure. Hospital stay was also less (1-2 days) in laparoscopy and more (≥3 days) in laparotomy, duration of operation was shorter (20-30min) in laparotomy and comparatively longer (30- 60 min) in laparoscopy. Previous surgery was done on 25% and 52.17% patients who underwent laparoscopy and laparotomy respectively. Previous ectopic pregnancy was diagnosed on 8.33% and 47.83% of laparoscopy and laparotomy patients respectively. Moreover, previous PID was found in 5.55% patients who underwent laparoscopy and none who underwent laparotomy. 2.77% of patients who underwent laparoscopy had a history endometriosis. Recovery to normal activity was early in laparoscopy and late in laparotomy. Moreover, 27 (67.5%) patients conceived among 40 who underwent laparoscopy, and 3 (15.78%) patients conceived among 19 who underwent laparotomy. Conclusion: The management of ectopic pregnancy with laparoscopy may be the most helpful operation with the highest possible level of safety and effectiveness. Laparoscopy has both a diagnostic & therapeutic role in ectopic pregnancy. Laparoscopy is feasible and safer than laparotomy in surgical management of ectopic pregnancy.

Study of Risk Factors in Patients of Pelvic Inflammatory Diseases

Number of risk factors has been associated with pelvic inflammatory disease, such as age, previous sexually transmitted infection, previous PID, multiple sexual partners, or an intrauterine contraceptive device. Women who use an intrauterine device for contraception are at least 2-4 times more likely to develop PID than non-users. Women who have had PID are twice as likely to develop the infection as those who have never had it. A history of a prior uncomplicated gonococcal infection is more common among women with PID than among women without disease. The present cross- sectional study was conducted in J.N. Medical College and Hospital (J.N.M.C.H.), Aligarh Muslim University, Aligarh. Permission for doing the study was taken by the Board of Studies in the Department of Community Medicine, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh. The study was carried out for a period of one year, from 1st August 2001 to 31st July 2002. The present study was carried out among ever married females in the reproductive age group of 15 to 49 years. Women, who gave positive history of PID, were asked to give their consent for the study. Their refusal was taken as exclusion criteria. Females with PID who were menstruating or who had taken antibiotic within the previous month were also excluded from the study. A total of 350 ever married females were selected from the Gynaecology OPD of J.N. Medical College Hospital (n=170), Urban Health Training Centre (n=100) and Rural Health Training Centre (n=80).A detailed clinical history and clinical examination were recorded on a pre-formed and pre tested proforma. All the females under study were subjected to per vaginal examination. The percentage of those female was more who used any cloth during menstruation. Out of 350 patients, 7.4% ga ve history of T.B, 24% gave history of previous episodes of PID, 12.0% gave history of MTPs/D&Cs. 5.1% had adopted IUCDs as a method of family planning.1.71% cases gave history of removal of IUCDs because of some complications. 75.0% of 80 cases (who adopted family planning) used IUCDs, OCPs and ligation. IUCDs, OCPs, ligation and irregular use of condoms probably increase chances of PID.

Lateral safety enhancement in a full dynamic vehicle model based on series active variable-geometry suspension

Today, the importance of providing safety and stability while paying attention to the ride comfort and providing road holding is of paramount importance. This issue has become more important due to the many accidents related to vehicle rollover. In this article, an attempt has been made to reduce the risk of rollover prevention of the vehicle while paying attention to the needs of the occupant and the road. In this research, an attempt has been made to reduce the overall acceleration of the GT vehicle by using a series of active variable geometry suspensions and by using a variety of control strategies such as Fuzzy PID, LQR, Sliding mode. In previous works, PID and Skyhook controllers have been used. However, in this study, the choice of the controllers is based on attention to accuracy and optimization while pay attention to control aims. This study was performed in conditions of severe asymmetric roughness and cornering maneuvers. The examination of the results shows an improvement of more than 20% for the goal of vehicle stability while providing other suspension goals. This performance improvement occurs with the effect of suspending variable geometry along with the use of a suitable controller. It should also be noted that the improvement achieved by consuming energy is far less than other suspensions, which is the strength of the research.

P18.02: Prevalence of negative 'sliding sign' in low‐risk population: a feasibility study

The prevalence of a ‘negative sliding sign’ in the low risk population is not known. Our aim is to determine the prevalence of a ‘negative sliding sign’ in low-risk women. An ongoing prospective study. Women attending the gynecology service at Nepean Hospital who were deemed low-risk for rectouterine adhesions were included in the study (i.e. nil previous or current history of endometriosis or PID, nil chronic pelvic pain, nil history of infertility or fertility treatment, nil previous pelvic surgery). Power calculation has predetermined a study size of n=303 women is required. Each woman was assessed for the presence of ‘sliding sign’ on transvaginal ultrasound at the both the retro-cervix and posterior uterine fundus. When the ‘sliding sign’ is considered positive in both of these anatomical regions (RC and PUF), the POD is recorded as ‘not obliterated’. If either of these anatomical regions demonstrates that the anterior rectal wall or rectosigmoid does not glide smoothly over the RC or PUF, respectively, then the ‘sliding sign’ is considered negative, and the POD is recorded as ‘obliterated’. Each woman was also assessed for ovarian mobility or presence/absence of an ovarian endometrioma. 613 women were recruited. 236 were excluded due to the presence of previous PID and/or endometriosis, 4 were excluded from this study as they were concerned about the safety of TVS in early pregnancy, 124 due to previous pelvic surgery, 21 due to previous fertility treatment/subfertility and 22 as they were beyond 12 weeks gestation. We noted that the real-time ultrasound based ‘sliding sign’ was positive in all 206 women and therefore the POD was recorded as non-obliterated. The ovaries were noted to be mobile in all cases as well. Although this is an ongoing study, the preliminary results suggest that the prevalence of POD obliteration on ultrasound evaluation in the low-risk population is negligible.

MIMO PI Controllers for LTI Systems with Multiple Time Delays Based on ILMIs and Sensitivity Functions

In this paper, a MIMO PI design procedure is proposed for linear time invariant (LTI) systems with multiple time delays. The controller tuning is established in two stages and guarantees performances for set-point changes, disturbance variations, and parametric uncertainties. In the first stage, an iterative linear matrix inequality (ILMI) approach is extended to design PI controllers for systems with multiple time delays without performance guarantee, a priori. The second stage is devoted to improve the closed-loop performances by minimizing sensitivity functions. Simulations results carried out on the unstable distillation column, the stable industrial scale polymerization (ISP) reactor, and the non-minimum phase 4-tank benchmark prove the efficiency of the proposed approach. A comparative analysis with the conventional internal model control (IMC) approach, a multiloop IMC-PI approach, and a previous ILMI PID approach proves the superiority of the proposed approach compared to the related ones.

Frequency of Tubal Ectopic Pregnancy and Mode of Management at Al-Thawra General Modern Hospital

Objective: To determine the frequency of tubal ectopic pregnancy and to evaluate the epidemiological and common predisposing factors in cases study. To determine the mode of management of tubal ectopic pregnancy. Study Design: This is a prospective descriptive analytic study carried out from 1 January 2013 until 31 December 2013 at obstetric and gynecological unit at Al-Thawra Hospital in Sana’a, Yemen. Results: Total number of deliveries from the 1st of January 2013 till the 31st of December 2013, were a total of 9330 deliveries, out of which 103 women had tubal ectopic pregnancy creating an incidence of 1.1% of the total deliveries with a ratio of 11/1000 live births. The mean age of the patients was 27.8 yrs and ranged between 17-40 years of age. It was most common in multipara with a percentage of 78.67 54.4% of women were Qat chewers and smokers. It was more commonly found in women of low economic status with 90.3%. 30.1% of women with it had a history of abortion, 70.9% had a history of pelvic inflammatory disease, 20.8% had a history of an abdominopelvic surgery, 11.7% were using intrauterine device and 5.8% were using progesterone-only pills, 1.9% had a history of tubal sterilization, 88.3% presented with abdominal pain, 72.8% gave a history of amenorrhea, 63.1% presented with vaginal bleeding, 79.6% presented with hemodynamic instability, 86.5% were treated surgically, and 14.5% were treated medically using Methotrexate. The surgical treatment was salpingectomy in 90.4%, and 6.6% was salpingostomy. There were no maternal mortalities. Conclusion: The most common risk factors found in patients with tubal ectopic pregnancy were previous abortions and PID. The majority of the patients were treated surgically as they were lately presented in a state of hemodynamic instability. 14.5% were treated medically and this proved to be very effective.

Study on Risk Factors, Clinical Presentation & Operative Management of Ectopic Pregnancy

Introduction: Ectopic pregnancy is a major clinical problem in gynaecology because it is often difficult to diagnose as the patient present in different ways. An accurate history taking and physical examination is considered to be most important in the diagnosis of ectopic pregnancy. There are two treatment options, medical or surgical. Surgical treatment is the fastest treatment for ectopic pregnancy though surgical management decreased from approximately 90% to 65%1. Surgery may be the only treatment option if there is internal bleeding. In the medical treatment group, 15% of cases were categorized as failures and required surgery1.Objectives: This study was conducted in the department of obst and Gynae of Dhaka Medical College Hospital from January 2005 to June 2005 in an attempt to find out the risk factors of ectopic pregnancy, the way of presentation and to analyze the operative treatment of ectopic pregnancy.Materials and Methods: A total 50 consecutive patients who were clinically suspicious of ectopic pregnancy were included in this study between January 2005 to June 2005. Patients who were clinically suspicious of EP and also supported by positive urinary pregnancy tests, beta hCG and no intrauterine gestational sac in ultrasonography were included in this study. Detailed discussion about the study was done with the patient and then informed verbal consent was taken from them. Detailed history about patient profile, presenting symptoms, any risk factors and clinical examination done and the findings were recorded in the predesigned data collection sheet. Data was expressed in terms of frequencies and percentagesResults: Most of the patients were in the age group of 20-30 years and 38% of low parity (para- 1).Previous miscarriage, infertility,IUCD users and PID identified as the risk factors of ectopic pregnancy— 42% patients had history of previous abortion or MR, period of infertility 22%, pelvic infection 12%, IUCD users 16%. In this study acute abdominal pain after a short period of amenorrhoea was found to be the main symptoms in ectopic pregnancy—100% patients were presented with lower abdominal pain, 70% with period of amenorrhea and 50% patients with per vaginal bleeding. All the patients were presented with acute condition and were surgically managed fastest treatment. At the time of operation 84% of ectopic tubal pregnancy were found ruptured, 10% were tubal abortion and 4% unruptured. Sites of ectopic pregnancy were ampullary 50%, isthmic 20%, fimbrial 10%.Conclusion: Most of the patient presented in acute condition with the classical features of ruptured ectopic pregnancy. Near half of the patient were in younger age group (26 – 30 years) having risk factors like history of previous abortion/MR 42%, infertility 22% use of IUCD 16%, PID 12%. More then three forth( 84%) of cases were diagnosed as ruptured ectopic during operation. Operative management was done on the basis of site of ectopic and parity of the womanBangladesh J Obstet Gynaecol, 2013; Vol. 28(1) : 9-14

Роль циклической витаминотерапии как негормонального метода восстановительного лечения нарушений менструального цикла после перенесенных воспалительных заболеваний органов малого таза

Intensity of generative functions violations depends on the frequency of the transferred inflammatory diseases of the pelvic organs (pelvic inflammatory disease), their etiology, treatment tactics and approaches to rehabilitation. With the increase in the number ofepisodes of the disease increasing, the frequency of tubal infertility and ectopic pregnancy also rises. The most characteristic effects of deferred PID are different forms of menstrual disorders. The inclusion in the program of treatment and prevention of disorders of vitamins and minerals of the menstrual cycle is a promising direction of finding an effective and safe approach to therapy. The results of a prospective study of the effectiveness of the two-phase vitamin-mineral complex Ciklovita® used by patients of reproductive age with oligomenorrhea, which developed after previous PID indicate the feasibility of its application.

Model-based PI–fuzzy control of four-wheeled omni-directional mobile robots

The purpose of this study is to suggest and examine a PI–fuzzy path planner and associated low-level control system for a linear discrete dynamic model of omni-directional mobile robots to obtain optimal inputs for drivers. Velocity and acceleration filtering is also implemented in the path planner to satisfy planning prerequisites and prevent slippage. Regulated drivers’ rotational velocities and torques greatly affect the ability of these robots to perform trajectory planner tasks. These regulated values are examined in this research by setting up an optimal controller. Introducing optimal controllers such as linear quadratic tracking for multi-input–multi-output control systems in acceleration and deceleration is one of the essential subjects for motion control of omni-directional mobile robots. The main topics presented and discussed in this article are improvements in the presented discrete-time linear quadratic tracking approach such as the low-level controller and combined PI–fuzzy path planner with appropriate speed monitoring algorithm such as the high-level one in conditions both with and without external disturbance. The low-level tracking controller presented in this article provides an optimal solution to minimize the differences between the reference trajectory and the system output. The efficiency of this approach is also compared with that of previous PID controllers which employ kinematic modeling. Utilizing the new approach in trajectory-planning controller design results in more precise and appropriate outputs for the motion of four-wheeled omni-directional mobile robots, and the modeling and experimental results confirm this issue.

Deoxyribonucleic acid of Chlamydia trachomatis in fresh tissue from the Fallopian tubes of patients with ectopic pregnancy

Objectives The role of persistent chlamydial infection of the Fallopian tubes in ectopic pregnancy is still unresolved. Therefore, we examined tissue of the Fallopian tubes from patients with ectopic pregnancy for the presence of Chlamydia trachomatis. In addition, other markers of C. trachomatis infection implicated in the pathogenesis of tubal damage were studied including antibodies to heat shock protein 60 of chlamydial and human origin. Study design Fresh frozen tubal tissue from 55 patients with ectopic pregnancy in a hospital setting were examined for the presence of C. trachomatis DNA by polymerase chain reaction (PCR) and blood sample were analysed for antibodies to C. trachomatis including heat shock protein 60 (hsp60). Results Chlamydial DNA was not detected in any of the 55 tubal specimens using a commercial test, Cobas Amplicor, Roche, and an in-house real time PCR able to detect a few copies of the organism. Logistic regression showed that chlamydial IgG antibodies were more common in a subgroup of patients with previous PID than in controls (OR = 7.84, CI 1.78–34.6). Specific antibodies to hsp60 of chlamydial (OR = 7.00, CI 1.50–32.6) but not of human origin (OR = 2.13, CI 0.14–31.6) were associated with ectopic pregnancy in this group. Conclusions No evidence of persistent infection of C. trachomatis in the fallopian tubes at the time of ectopic pregnancy was found in this study.

Fractional robust control of main irrigation canals with variable dynamic parameters

A new method is proposed for controlling main irrigation canals with variable dynamical parameters based on robust fractional order controllers. A methodology for designing PID controllers robust to changes in the time delay and the gain is presented first. Then this method is generalized to design fractional controllers that exhibit the same robustness as the previous PID to time delay and gain changes, but are noticeably more robust to variations in the dominant time constant of the process. This method is applied to control main irrigation canals. Extensive numerical simulations using the dynamic model of a real canal were carried out. Then experimental results were obtained in a prototype canal that proved the effectiveness of the proposed control method in terms of performance and robustness.

Improved filtered-ɛ adaptive inverse control and its application on nonlinear ship maneuvering

The drawbacks of common nonlinear Filtered-ɛ adaptive inverse control (AIC) method, such as the unreliability due to the change of delay time and the faultiness existing in its disturbance control loop, are discussed. Based on it, the diagram of AIC is amended to accommodate with the characteristic of nonlinear object with time delay. The corresponding Filtered-ɛ adaptive algorithm based on RTRL is presented to identify the parameters and design the controller. The simulation results on a nonlinear ship model of “The R.O.V Zeefakkel” show that compared with the previous scheme and adaptive PID control, the improved method not only keeps the same dynamic response performance, but also owns higher robustness and disturbance rejection ability, and it is suitable for the control of nonlinear objects which have higher requirement to the maneuverability under complex disturbance environment.

Combining fuzzy, PID and regulation control for an autonomous mini-helicopter

This paper reports on the synthesis of different flight controllers for an X-Cell mini-helicopter. They are developed on the basis of the most realistic mathematical model currently available. Two hybrid intelligent control systems, combining computational intelligence methodologies with other control techniques, are investigated. For both systems, Mamdani-type fuzzy controllers determine the set points for altitude/attitude control. These fuzzy controllers are designed using a simple rule base. The first scheme consists of conventional SISO PID controllers for z-position and roll, pitch and yaw angles. In the second scheme, two of the previous PID controllers are used for roll and pitch, and a linear regulator is added to control altitude and yaw angle. These control schemes mimic the action of an expert pilot. The designed controllers are tested via simulations. It is shown that the designed controllers exhibit good performance for hover flight and control positioning at slow speed.

1172: Assessment of cystic adnexal masses

The sonographic assessment includes a transabdominal and an endovaginal exam or endorectal in virginal patients. The endocavitary probe allows identification of tender organs and can assess the fallopian tubes, ovaries and sigmoid colon. Simple cysts are the most common ovarian masses. It is anechoic, smoothly marginated, unilocular with posterior enhancement. Usually functional and disappear within two cycles. If it does not resolve after three cycles, it is not functional. Theca lutein cysts are small, bilateral cysts associated with PCOD, mole or ovarian stimulation and resolve after treatment. Para-ovarian and para-tubal cysts are remnants of the Wolffian duct. They are mistaken for ovarian cysts. They are small, thin walled, nontender, unchanging in size and separate from the ovary. Complex ovarian masses can be benign or malignant. The primary criteria for a malignant ovarian mass usually are a diameter >4 cm, thick wall or septum >3 mm, large solid or mostly solid mass or nodularity. Ascites, large nodes or a mass fixed or nonmovable on EV exam, are signs of extension locally from the primary mass. A serous cystadenoma or cystadenocarcinoma is the most common ovarian neoplasm. Masses are thin walled, unilocular and may have thin septa or papilla. The malignant ones are thick walled, multilocular with multiple papilla and ascites. Mucinous cystadenoma or carcinoma comprises 20% of all benign and 10% of malignant ovarian masses. They are usually very large, often exceeding 15 cm. They have multiple septa with low-level internal echoes due to the mucin. Hemorrhagic cyst is echogenic and as clot forms, fibrin bands appear as fine septations giving a fishnet appearance. Retracting clot is triangular. An endometrioma may have a varied appearance on US often with a ground glass appearance and low level echoes. There may be layering of echogenic material and the mass may look solid or cystic. The mass is usually tender to palpation with the EV probe. Ectopic pregnancy may have a wide variety of presentations. Echogenic free fluid does not always mean a ruptured ectopic. Dermoid cyst is the most common germ cell tumor. About 30% are malignant if present is a preadolescent. There may be fat-fluid levels, calcification, and an echogenic mass with shadowing and/or bright linear bands that may represent hair. Abscess. There is usually fever and increased white count with a multilocular mass with thick walls that is tender to the touch. The mass is nonmobile. Treatment is antibiotics and/or drainage. Hematosalpinx and hydrosalpinx may be called a septated ovarian cyst but in the correct scan plane the tubular nature of the mass is evident. It is separate from, but adjacent to the ovary with layering of echogenic debris, pus or blood. May be previous PID or tubal ligation. Ovarian torsion. The ovary is enlarged with small peripheral cysts. A larger cyst may also be present. No vascularity seen. If a small amount of flow is present then the ovary can be salvaged if it is untwisted. There may be increased flow if there has been inflammation or it has de-torted.

Transvaginal Hydrolaparoscopy (THL) for the Evaluation of Pelvic Anatomy in the Infertile Woman, a Review of the Initial Experience in the United States

Transvaginal Hydrolaparoscopy (THL) for the Evaluation of Pelvic Anatomy in the Infertile Woman, a Review of the Initial Experience in the United States

No effect of single dose ofloxacin on postoperative infection rate after first‐trimester abortion

In a double-blind stratificated, placebo controlled study the efficacy and safety of a single oral dose of ofloxanin (Tarivid) (400 mg) in preventing postabortal pelvic inflammatory disease (P-PID) in women with induced first-trimester abortions were assessed. The tablets were given 1 1/2-2 h before the abortion, and the women were followed one month after the operation. Group I consisted of 308 with previous PID. Ofloxacin tablets were given to 149 women and 159 women received placebo tablets. In the ofloxacin group 20 women (13.4%) and in the placebo group 27 women (17%) developed P-PID, a non-significant difference (p = 0.39). Group II consisted of 765 women without a history of PID. Ofloxacin tablets were given to 376 women and 389 women received placebo tablets. Thirty-five women (9.3%) in the ofloxacin group and 46 women (11.9%) in the placebo group developed P-PID, a non-significant difference (p = 0.26). A single oral dose of ofloxacin (400 mg) did not reduce the incidence of P-PID either among women with previous PID or among women without previous PID.

Historical linguistics Edited by Barron Brainerd (review)

REVIEWS929 Historical linguistics. Edited by Barron Brainerd. (Quantitative linguistics, 18.) Bochum: Brockmeyer, 1983. Pp. 236. DM 29.80. Reviewed by Anthony J. Naro, Universidade Federal do Rio de Janeiro The title of this book is somewhat misleading, even given the series name. The papers are devoted almost entirely to problems involving type change in the lexicon—or, in some cases, change over time in the frequency of use of lexical items. Most of the authors look to Morris Swadesh as the founder of this field of inquiry; they attempt to develop, modify, and apply his methodology in the light of facts or problems that arise in various language families. Nonetheless, the book presents some innovative techniques, and even some rare non-lexical, non-quantitative material. In the first article, 'Incorporating borrowing rates in lexicostatistical tree reconstruction' (1-24), Sheila M. Embleton provides a good (although obviously biased) survey of developments to date in the field. This part would have been much more useful if E had provided a balanced discussion of the many controversies and confusions of the 60's and early 70's, which still leave most linguists with severe doubts as to the validity of any Swadesh-like methodology . In any event, she reviews a series of possible revisions to Swadesh's original assumption that the rate of change is a constant multiplied by the number of remaining cognates; she also discusses David Sankoffs method, originally intended for use in biology, of reconstructing an evolutionary tree based on a similarity measure that considers only proportions of cognates, and postulates constant probabilities of internal word replacement and external word borrowing. In a computer simulation of Sankoffs method, E finds that satisfactory reconstructions can be achieved with a 200-word list—which, however , need no longer be constrained to rule out borrowing, since this factor is now explicitly considered. She goes on to propose modifying Sankoffs method to allow replacement and borrowing rates to differ for different languages and language pairs. Finally, she proposes to test the resulting method on real data from the Germanic languages; but this has not yet been carried through. Abstract, intuition-oriented linguists, on the one hand, will of course reject E's paper (as well as most of the others in the volume), since they would never countenance the idea of measuring similarity between languages, or any other significant property, on the basis of proportions of cognates. Real-world, data-oriented linguists, on the other hand, will be severely disappointed by the lack of any empirical proof of goodness of fit. E (p. 3) approvingly quotes Sankoff 1972 as having stated, correctly, that in models like that under consideration, 'any degree of deviation is predicted to occur in a certain proportion of cases'. However, it is wrong to infer from this, as E does in her next sentence, that empirical evidence is therefore in effect irrelevant. If the model is good, the proportion of cases in which significant deviation occurs will be low. In fact, the only reason Sankoffs models in the area of linguistic variation are now so widely accepted is precisely the fact of their good fit to real data in a large number of cases. Until such time as parallel results can be presented for lexicostatistic models, linguists are fully justified in remaining skeptical. ? stochastic model for language change' (25-49), by Brainerd, uses the same basic Swadesh-like framework, but different mathematical techniques. B first discusses, unfortunately without explicit reference, Whinnom's relexification hypothesis (1956, 1965), which postulates that pidgins arise from previous pid- 930LANGUAGE, VOLUME 60, NUMBER 4 (1984) gins as a result of shift in lexical items from one language to another, while retaining essentially the same reduced grammar. This would seem to be the ideal linguistic site for application of lexical methods, since the syntax is assumed to be constant, but one critical point must not be forgotten: the theory of relexification is intended to explain only the derivation of one pidgin from another—it is irrelevant to the problem of the origin of pidginization. Thus relexification would be applicable to the transition from the original Romance (Portuguese) pidgin to English-based pidgins, but not to the...